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How do I create an average from a Ruby array?
... sum + el }.to_f / arr.size
=> 6.5
Note the .to_f, which you'll want for avoiding any problems from integer division. You can also do:
arr = [5, 6, 7, 8]
arr.inject(0.0) { |sum, el| sum + el } / arr.size
=> 6.5
You can define it as part of Array as another commenter has suggested, but you...
Split string to equal length substrings in Java
...e last match.
Both lookbehind and \G are advanced regex features, not supported by all flavors. Furthermore, \G is not implemented consistently across the flavors that do support it. This trick will work (for example) in Java, Perl, .NET and JGSoft, but not in PHP (PCRE), Ruby 1.9+ or TextMate (b...
How do I read the contents of a Node.js stream into a string variable?
...pt up with node.js, and I cannot delete this answer because it is marked "correct on this question". If you are thinking of down clicking, what do you want me to do?)
The key is to use the data and end events of a Readable Stream. Listen to these events:
stream.on('data', (chunk) => { ... });
str...
Table is marked as crashed and should be repaired
I am getting this error in wordpress phpMyadmin
6 Answers
6
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What is the function of the DBMDL File in VS database project
...make out, it is a serialized file of your db model and is used as a cache for improving the performance of deployment. It is unique per user thus should not be checked into source control.
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Open the file in universal-newline mode using the CSV Django module
...d in Django to parse a CSV file in Python using the csv module. It's working on Windows, but on Mac it gave me this:
1...
Listing only directories using ls in Bash?
This command lists directories in the current path: ls -d */
26 Answers
26
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Why is creating a Thread said to be expensive?
The Java tutorials say that creating a Thread is expensive. But why exactly is it expensive? What exactly is happening when a Java Thread is created that makes its creation expensive? I'm taking the statement as true, but I'm just interested in mechanics of Thread creation in JVM.
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What's the difference between a Future and a Promise?
...erence between Future and Promise ?
They both act like a placeholder for future results, but where is the main difference?
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What are the differences between B trees and B+ trees?
In a b-tree you can store both keys and data in the internal and leaf nodes , but in a b+ tree you have to store the data in the leaf nodes only .
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